Verification of tracks made of Lorena using GEFS mean fields

November 13, 2019

I made six tracks of Hurricane Lorena. Additionally, within 384 hours of cyclogenesis, there were four instances, when I missed cyclogenesis entirely. There was a significant bias to the left of actual track, possibly due to incorrect accounting for nearby Mario.

As of this analysis, best track positions are available September 15, 06Z thru September 22, 12Z, and as such, position comparisons are possible only for this timespan.

Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2".

In the six tracks, formation times ranged between September 16, 06Z and September 24, 06Z. Average was September 18, 09Z and median was September 16, 18Z.

In the ten cases (6 tracks and 4 complete misses), peak intensity ranged between Category -2 and Category 5. Average was Category 1.00 and median was Category 0.50.

In the six tracks, dissipation times ranged between September 20, 06Z and October 3, 12Z. Average was September 26, 07Z and median was September 25, 09Z.

At the lead time of 1 day (24 hours), there were 0 hits, 0 false detections and 0 misses. No available position comparisons.

At the lead time of 2 days (48 hours), there were 0 hits, 0 false detections and 1 miss. No available position comparisons.

At the lead time of 3 days (72 hours), there were 0 hits, 0 false detections and 1 miss. No available position comparisons.

At the lead time of 4 days (96 hours), there were 0 hits, 1 false detection and 2 misses. 1 available position comparison produces an average error of 86 nautical miles.

At the lead time of 5 days (120 hours), there were 1 hit, 0 false detections and 2 misses. 1 available position comparison produces an average error of 171 nautical miles.

At the lead time of 6 days (144 hours), there were 1 hit, 2 false detections and 2 misses. 3 available position comparisons produce an average error of 238 nautical miles.

At the lead time of 7 days (168 hours), there were 2 hits, 1 false detection and 1 miss. 3 available position comparisons produce an average error of 254 nautical miles.

At the lead time of 8 days (192 hours), there were 3 hits, 0 false detections and 1 miss. 3 available position comparisons produce an average error of 290 nautical miles.

At the lead time of 9 days (216 hours), there were 3 hits, 0 false detections and 0 misses. 3 available position comparisons produce an average error of 380 nautical miles.

At the lead time of 10 days (240 hours), there were 2 hits, 2 false detections and 1 miss. 2 available position comparisons produce an average error of 473 nautical miles.

At the lead time of 11 days (264 hours), there were 2 hits, 2 false detections and 2 misses. 2 available position comparisons produce an average error of 615 nautical miles.

At the lead time of 12 days (288 hours), there were 2 hits, 1 false detection and 2 misses. 2 available position comparisons produce an average error of 726 nautical miles.

At the lead time of 13 days (312 hours), there were 1 hit, 3 false detections and 2 misses. 2 available position comparisons produce an average error of 568 nautical miles.

At the lead time of 14 days (336 hours), there were 2 hits, 2 false detections and 2 misses. 2 available position comparisons produce an average error of 594 nautical miles.

At the lead time of 15 days (360 hours), there were 1 hit, 2 false detections and 2 misses. 1 available position comparison produces an average error of 381 nautical miles.

At the lead time of 16 days (384 hours), there were 1 hit, 2 false detections and 2 misses. 1 available position comparison produces an average error of 651 nautical miles.

Circle coloration scheme